Which condition can result in dizziness or syncope in heart failure patients?

Choosing low cardiac output as the correct answer highlights the relationship between heart function and symptoms experienced by patients with heart failure. Low cardiac output occurs when the heart is unable to pump sufficient blood to meet the body’s demands. This underpins several critical physiological changes, including reduced perfusion to vital organs such as the brain, which can lead to dizziness or syncope (fainting).

In heart failure, especially during exacerbations or when there is additional stress on the heart, the compromised ability to circulate an adequate volume of blood can precipitate these symptoms. Dizziness can occur due to insufficient blood flow to the brain, while syncope can result from sudden drops in blood pressure associated with low output states, particularly during activities or changes in position.

The other conditions listed, while they may have implications for heart failure, do not directly lead to dizziness or syncope with the same frequency or mechanism as low cardiac output does. For example, hypertension typically leads to the opposite issue: elevated systemic vascular resistance, which can exacerbate heart failure but does not directly cause dizziness as a consequence of cerebral hypoperfusion. Hypervolemia relates to fluid overload, which could worsen heart failure symptoms but does not inherently cause dizziness or syncope directly. Coronary artery